do skunk2 IM use the factory IAC?

 

I think you have to modify it to use it. From what i have read, the engineer working on that project for Skunk2 left prior to finishing it and then it was just rigged to get it into production, so it takes a bit of custom fab to get it to work.

 

do you even have to use the IAC?

 

disconnect it from the harness and see what happens

yes it is necessary. when the motor is warmed up the IACV takes over idle duties from the FITV

 

Yes, they use it. No, you don't have to modify it. It does sit behind the manifold instead of in front of it like it does on the stock manifold. If you have a 5th gen(maybe a 4th gen, too....I don't know), you need to put the manifold on first. When I installed the iacv on the manifold first, it got in the way of the firewall, and I had to take it back off.